87784640 has 56 divisors (see below), whose sum is σ = 209866992. Its totient is φ = 34974720.

The previous prime is 87784637. The next prime is 87784657. The reversal of 87784640 is 4648778.

It is a super-2 number, since 2×87784640² = 15412286039859200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 87784591 and 87784600.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 126695 + ... + 127385.

Almost surely, 2^87784640 is an apocalyptic number.

87784640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 87784640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104933496).

87784640 is an abundant number, since it is smaller than the sum of its proper divisors (122082352).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

87784640 is a wasteful number, since it uses less digits than its factorization.

87784640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1105 (or 1095 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 44.

The square root of 87784640 is about 9369.3457615780. The cubic root of 87784640 is about 444.4328759952.

The spelling of 87784640 in words is "eighty-seven million, seven hundred eighty-four thousand, six hundred forty".